Ruckman Rory Lobb has picked up a third injury of the year, and will miss at least the next month for Greater Western Sydney.
Lobb's place against Brisbane at the Gabba on Saturday is likely to go to either Dawson Simpson or youngster Matt Flynn as the Giants bid for a third straight win.
We've got to be really careful that it doesn't turn into a bigger issue later in the year.Leon Cameron
GWS had feared the big man might have suffered a punctured lung when he was taken to hospital during the win over Gold Coast last time out.
He was cleared at that time of significant damage, but after reporting pain during the club's bye week he was scanned again and found to have a small fracture in his thoracic spine.
The West Australian has been out of luck this year, having battled a groin issue in the pre-season, then suffered bone bruising in his knee against Sydney in round three that put him out for a further month.
Coach Leon Cameron said of his latest setback: "The crack is really small but it's in one of those really awkward spots in his back. We've got to be really careful that it doesn't turn into a bigger issue later in the year.
"It's really disappointing because it was his fifth game back from his knee, and he was just starting to get some momentum, but unfortunately he's not going to be playing for four or five weeks.
"He wants to get some continuity with the midfielders too, and that's what we want as a club, but that's what happens."
Forward Daniel Lloyd is expected miss 4-6 weeks after straining his medial ligament against the Suns.
But the Giants have had better news over vice-captain Stephen Coniglio (concussion), who has been cleared to face the Lions on Saturday.
GWS are 1/3 to beat Brisbane, who are 5/2.
The Giants are 93/100 conceding a 23.5-points start.
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